Overview of sensor signal paths

The need to detect and measure pressure and weight is a very common requirement for modern industrial control and system monitoring. Pressure measurement is especially important, as it is also used indirectly to measure flow, altitude, and other properties. Pressure- and weight-measurement devices can be regarded as "force sensors," since force is the property that affects the transducers' outputs. The applications for force sensors are vast and range from vacuum gauges, to heavy machinery weigh scales, industrial hydraulic equipment, and manifold absolute pressure (MAP) sensors for internal-combustion engines. Each application has its own diverse needs for precision, accuracy and cost.

This tutorial explains the sensor signal chain for the most popular sensor transducer types for pressure, temperature, current, light and proximity sensing. The article introduces the intricacies of selecting a signal path. Example circuits and block diagrams help the reader select an optimal set of parts to meet their design needs.

What is a sensor?
A device that receives and responds to a stimulus or signal. Sensors measure real-world conditions, such as heat or light, and then convert this condition into an analogue or digital representation.